Alcohol, Drugs, and Driving Flashcards
7 cards from real Washington State Knowledge Test practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Alcohol, Drugs, and Driving flashcards as text
In Washington, a driver 21 or older is considered impaired by marijuana with a THC blood concentration of at least:
Answer: 5 nanograms per milliliter
Washington's per se THC limit for drivers 21 and older is 5.0 ng/mL of active THC in the blood.
What is the legal THC blood limit for a Washington driver under age 21?
Answer: Any amount above 0.00 ng/mL
Drivers under 21 may not drive with any measurable THC in their blood.
A commercial driver operating a commercial motor vehicle in Washington is considered impaired at a BAC of:
Answer: 0.04%
The BAC limit for drivers operating a commercial vehicle is 0.04%, half the standard adult limit.
Under Washington's implied consent law, what happens if you refuse a breath test after a lawful DUI arrest?
Answer: Your license is revoked for at least one year
Refusing a breath test results in license revocation for at least one year, and the refusal can be used as evidence in court.
Which of the following medications could legally result in a DUI charge if it impairs your driving?
Answer: Any drug, including over-the-counter and prescription medicines
Being impaired by any drug, even one legally prescribed or bought over the counter, can lead to a DUI.
You took a cold medicine whose label warns it may cause drowsiness. What should you do?
Answer: Avoid driving until you know how it affects you
Drowsiness warnings mean the medicine can impair driving, so you should not drive until you are sure it is safe.
Combining alcohol with other drugs, such as sedatives, generally:
Answer: Multiplies the impairing effects
Alcohol mixed with other drugs often produces a stronger combined effect than either one alone.
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